1. Field of the Invention
The present invention relates to a device for the incremental height adjustment of an attachment or deflection point for a safety belt or the like. In particular, the present invention utilizes a leaf spring member combined with the adjustment element into one module clamped to a guide bar. The improvement of the present invention allows a construction with fewer pieces and thus, less cost.
2. Background and Summary of the Invention
Devices serving similar purposes have been well known in the prior art. Aside from some very complicated designs, such devices essentially comprise three modules, namely, a guide bar, an adjustment element and a spring element. The adjustment element is designed in such a way that it is maintained and guided on, or even in, the guide bar. Up to now this could only be done by giving it a specific shape. For example, adjustment elements in the shape of a sleeve surrounding the guide bar are known in connection with flat as well as channel-like guide bars as disclosed in U.S. Pat. No. 4,640,550 to Hakansson. Furthermore, flat adjustment pieces are known which only derive fixation and guidance in connection with a separate complementary piece or further connecting piece, for example a belt deflection (see German Published, Non-examined Patent Application DE-OS 36 18 973). With all this, the singular function of the spring element is to maintain a desired arresting position.
Limitation to only the said three modules surely already is an important step in the direction of efficient production and assembly. In spite of this, however, the design of the adjustment element, if it is to operate without further connecting pieces, appears to be too complicated, or the fact that full operability can only be attained with the aid of further connecting pieces makes manufacturing and assembly expensive and cumbersome.
This is the point of departure for the present invention. Its object is to improve a device of the type mentioned above in such a way that production and assembly are made simpler and less expensive. The device is intended to be adjustable without additional connecting pieces.
This object is attained by making the spring element a leaf spring essentially extending over the length and width of the adjustment element and being combined with the adjustment element into one module clamped to the guide bar.
As shown, in accordance with the intent of the invention, the adjustment element and the spring element are to be matched to each other and connected with each other in a special way, namely into a special module. The invention assumes that the spring element, in addition to arresting purposes, can be used for other functions, i.e. for fixing and guidance of the adjustment element. The basis for this idea is the recognition that the adjustment element is not evenly stressed over its entire circumference and thus, need not have the same dimensions over its entire circumference. It is therefore sufficient to design that portion of the adjustment element, which is not tensionally stressed and which only provides an interlocking connection with the guide bar, considerably weaker and in particular with an ordinary thickness of the sheet metal. In accordance with the invention, a leaf spring is intended for this area, which is to be combined with the adjustment element into a new functional unit. In this way, the leaf spring is not only used for arresting, but additionally for fixing and guiding the adjustment element on or in the guide bar.
If the guide bar is flat, the leaf spring must be installed at the front and connected with the adjustment element in the area of the slot, which for practical reasons is done in the end sections. In the case of a channel-shaped guide bar, the leaf spring may also be disposed at the front, and alternatively, also on the back, in which case the leaf spring is then supported against the bottom of the guide bar. In each case the leaf spring is directly connected with the adjustment element and completes its shape. In this way the adjustment element can be shaped very simply at the core and in particular, can be of a flat shape. Such a shape can be achieved easily by stamping, or moderate shaping, out of customary strip steel. Connection with the leaf spring can even be made in some cases prior to pushing it on the guide bar, but in others only when placing it on the guide bar. This is in particular applicable if the leaf spring is intended to be disposed at the front of a guide bar having a slot, and the adjustment element extends through the slot with a section, for example, an extruded threaded hole (for fastening a connection piece).
According to its complex tasks, the leaf spring may have areas or sections bent or prestressed in different ways, in particular those which are used for support and guidance along the guide bar and those which are used as an (elastic) connection to the adjustment element. Otherwise, the connection can be removable or fixed, which has no effect on the operation of the invention.
For practical reason, the adjustment element has at the beginning and/or end an edge or the like extending through the slot to connect it with the leaf spring. Advantageously, the edge has a slit or the like to receive a strip-like end section of the leaf spring.
According to another proposal, the edge is provided with a retaining stud or the like for clamping an end section of the leaf spring.
In a further embodiment of the idea of the invention, the edge has lateral extensions beyond the slot. The proposed extensions act as stops, during crosswise movements for disengaging the adjustment element and in the course of deformation of the guide bar in case of an impact. Thus, the extensions have the dual function of a limitation of lift in the normal case and of a stabilizer in the case of an accident. Guide surfaces may be provided on the adjustment element to insure smoother operation.
The foregoing and other advantages of this invention will become apparent to those skilled in this art as consideration is given to the following detailed description taken in conjunction with the accompanying drawings.